Partners in Health sent us images of the Hôpital Universitaire de Mirebalais in Haiti, which will be the world's largest solar-powered hospital when it is officially unveiled in March this year. On an average day, the 1,800-strong solar crown on the hospital's

Partners in Health sent us images of the Hôpital Universitaire de Mirebalais in Haiti, which will be the world's largest solar-powered hospital when it is officially unveiled in March this year. On an average day, the 1,800-strong solar crown on the hospital's roof will meet all of the building's daytime energy needs, while on brighter days it is expected to produce a surplus that will boost the flailing national grid. The nation's first teaching hospital will also create 800 new jobs in the country that was struck by a devastating earthquake that killed and displaced thousands of people a few years ago.

Haiti’s electricity supply is intermittent, which spells big trouble for a hospital that needs round-the-clock power to keep machines running and medicines cool. “It’s not great if you’re a surgeon and you have to think about getting the generator going,” PIH co-founder Paul Farmer said at a recent lecture at the Harvard School of Public Health, according to the company. Which is why they decided to use solar power for the new teaching hospital located approximately 30 miles north of Port-au-Prince.

But that decision is not as easy as it might seem. While Haiti has plenty of sun, too much of a good thing can actually reduce the efficiency of solar panels. To mitigate this problem, PIH painted the roof white to deflect some of the sun’s rays back on to the panels, which are floated one foot above the roof’s surface. A sun chart provided by the University of Oregon allowed the company to orient the array in just the right position to maximize the panels’ efficiency. Already the hospital has produced 139 MW, which, as PIH puts it, is enough energy to charge 22 million smartphones. Once completely online in March it is expected to divert 210 metric tons of CO2 emissions and slash operating costs of a similar facility by $379,000 each year.